Do the leukocytes in the surface secretion on the adenoid have an immunological function?

To elucidate whether leukocytes in the surface secretion on the adenoid have a potential immunological function, imprint samples of surface secretion were obtained from the adenoid of 11 children and the corresponding mucosal area of 10 adults. May-Grünewald-Giemsa staining was used for evaluation of cell morphology and spatial relations, and immunohistochemical staining for identification of granulocytes, B cells, T cells and macrophages. The children's imprints showed large numbers of leukocytes, with mononuclear cells in the majority. The adults' imprints were characterized by moderate numbers of epithelial cells and few leukocytes. In six out of seven adenoid secretions successfully analysed with all four CD antigens, there was the simultaneous presence of granulocytes, B cells, 1 cells and macrophages. This was the case in one of nine analysable adult secretions. The CD-positive cells were often seen in juxtaposition, in clusters of two to 10 cells, as well as in contact with leukocytes of unknown CD antigenicity and epithelial cells. The simultaneous presence in the secretion of morphologically intact and CD antigen-presenting leukocytes in juxtaposition could indicate a potential immunological function of these cells.